Heard was reportedly spotted earlier this week with a seriously-big ring on her left hand. The famously private couple hasn't confirmed anything, but sources reportedly told Us Weekly it's on.

"The proposal happened a while ago," an insider told the magazine. "She just didn't wear the ring." (Celebuzz reported news of an engagement on Thursday.)

The actors met while filming "The Rum Diary" and confirmed they were in a relationship in June 2012, not long after Depp announced his split from longtime partner Vanessa Paradis, with whom he has two kids, daughter Lily-Rose, 14, and son Jack, 11.

The couple will reunite on-screen later this year in "London Fields," a crime thriller based on the 1989 novel by Martin Amis. Depp has a cameo on the movie, which also stars Billy Bob Thornton, Jim Sturgess, and Theo James.